Objective: The objective of this study is to identify nutritional risk factors for adult cancers, particularly breast, prostate, and colon. Exposures of primary interest include diet, alcohol ingestion, physical activity, height, weight, and body fat distribution. Relations of exposures that may be affected by diet, such as serum lipids and sex hormones, to cancer also are of interest. (See related project Z01 CN 00146-08 CPSB.) Background: The Framingham Offspring Study is an ongoing prospective cohort study of 5,135 children of the original Framingham Heart Study cohort members. Since the cohort was initiated in 1972, members have been examined at five interval visits (cycles) to identify behavioral and physical characteristics that are risk factors for coronary heart disease, stroke, and other cardiovascular endpoints. In 1985, DCPC funded a contract to procure a file identifying all cancers diagnosed among participants of the offspring study partially through cycle 3. In 1994, a second contract was funded to update this file through cycle 5. Progress: Because participants in the Framingham Offspring Study are relatively young, numbers of site specific cancers have not been sufficient to evaluate nutritional hypotheses. The contract to update the cancer file will be completed in December 1996. Ascertainment of breast cancers is complete through cycle 5 and analyses of the relation of alcohol ingestion to breast cancer risk are underway. Additionally, a proposal to evaluate the relation of diet to breast cancer has been approved by the Framingham Cancer Committee.